As fingerprint sensors are sensors for sensing human finger fingerprints, recently, the fingerprint sensors have been widely used as tools to enhance security in portable electronic devices such as mobile terminals, tablet PCs, etc. That is, since the registration or identification of a user has to be processed by the fingerprint sensors, data stored in the portable electronic devices is protected, and security breaches are prevented.
Meanwhile, in the portable electronic devices, a fingerprint sensor is integrated with a function of navigation which performs an operation of a cursor or pointer and this type of the fingerprint sensor is referred to as a biometric track pad (BTP). In other cases, the fingerprint sensor is integrated with a switching function through which a user inputs information.
Such as a fingerprint sensor is manufactured as a module, in which a fingerprint sensor, integrated circuits (ICs), bezels, etc. are integrated, and mounted on an electronic device.
Meanwhile, in order to mount the fingerprint sensors on various types of electronic devices, the fingerprint sensors are each manufactured as a module type including peripheral components or configurations. Here, the base material of the fingerprint sensor including the fingerprint sensor needs colors in order to match the color of an electronic device, on which the fingerprint sensor module will be mounted, and the color of the fingerprint sensor, or in order for any other reason.
To implement colors on the base material of the fingerprint sensor, a method, such as painting using colored paint, coating using ultraviolet rays (UV), etc., are generally used. However, when colors are implemented on the base material of the fingerprint sensor using a general method, there is a problem in which configurations and thicknesses of interlayers included in a film should be suitably ensured. When the thickness of the film is not fully formed, the implementation of colors is not easy, and also there is a high possibility of generating damage such as contamination, scratches, cracks, etc. The above damage negatively influences an image of a fingerprint sensed by the fingerprint sensor.
Meanwhile, in the fingerprint sensor, and more particularly, in the fingerprint sensor using a capacitive touch method, operability thereof can be changed according to a film thickness formed on the base material of the fingerprint sensor. Particularly, as the film thickness formed on a base material of the fingerprint sensor is greater, sensitivity of the fingerprint sensor is worse, and thus, there is a limitation for the film thickness to implement color thereon.
As described above, there is a tradeoff in general. That is, when an allowable thickness of the film is formed on the base material of the fingerprint sensor to implement color, the operability of the fingerprint sensor is worse, and on the contrary, when the film is formed to be a thin layer so that the operability of the fingerprint sensor is acceptable, desired colors are not obtained or resistance to abrasion is worse.
Recently, fingerprint sensor modules that are minimized and manufactured with a low cost and designed using a chip-on-flex (COF) or ball grid array (BGA) method have been developed in order to mount the fingerprint sensor modules on portable devices. In the fingerprint sensor module, an IC for sensing a fingerprint is separated from a sensing area.
The fingerprint sensor module includes a fingerprint sensor, and a bracket or substrate fixing the fingerprint sensor. Accordingly, a process of coupling the fingerprint sensor to the bracket, in which efficiency and productivity of the process is improved, and a process of the bracket to improve sensitivity are required.
Therefore, a fingerprint sensor module, in which a thickness from a sensing area of the fingerprint sensor to a cover at a final stage being in contact with a user's finger does not influence the function of an electronic device (e.g., the sensitivity of a fingerprint) and also there are no problems for an exterior and reliability of the electronic device, a portable electronic device including the same and a method of manufacturing the same are required.